Auger ice making machine



y 1967 A. J. ROSS 3,320,769

AUGER ICE MAKING MACHINE Filed May 24, 1966 5 sheets sheet 1 y 3, 1967A. J. ROSS 3,320,769

AUGER ICE MAKING MACHINE Filed May 24, 1966 5 Sheets-Sheet 2 y 1967 A.J. ROSS 3,320,769

AUGER ICE MAKING MACHINE Filed May 24, 1966 5 Sheets-Sheet 5 UnitedStates Patent 3,320,769 AUGER ICE MAKING MACHINE Anthony J. Ross, 52874th St., Holmes Beach, Fla. 33510 Filed May 24, 1966, Ser. No. 552,45818 Claims. (Cl. 62-354) This application is a continuation-in-part ofthe copending application of Anthony J. Ross, Ser. No. 510,298, filedNov. 29, 1965, and now abandoned.

This invention relates to ice making apparatus for producing a flake iceproduct.

The present invention relates to improvements in ice making apparatus ofthe type disclosed in my prior Patent 3,101,598 and having arefrigerated cylindrical freezing wall for freezing water in a layerthereon and a helical ice remover for removing ice from the freezingwall. Such ice making apparatus operates to freeze ice in a layer on thefreezing wall until the ice layer becomes sufficiently thick to beengaged by the rotating ice remover, and the ice remover then operatesto strip the ice from the freezing wall. However, in the prior icemaking apparatus, the ice remover sometimes tended to remove the icefrom a major portion or even the entire freezing wall at one time,thereby producing peak loads on the ice remover drive mechanism whichwere higher than the torque required when the ice layer is removed insmaller sections. Further, when the ice remover is in the form of anaxially expansible helical coil, considerably greater elongation of thecoil occurs when the coil engages and removes a major portion or all ofthe ice from the evaporator at one time.

An object of this invention is to provide an ice making apparatus of thetype having a helical ice remover for removing the ice from the freezingwall, and which is so arranged as to reduce peak loads on the iceremover drive mechanism.

Another object of this invention is to provide an ice making apparatusof the type having an ice remover in the form of an axially expansiblehelical coil for removing ice from the freezing wall, and which reducesthe change in the axial dimensions of the coil during removal of the icefrom the freezing wall.

Another object of this invention is to provide an ice making apparatushaving a helical ice removing device for removing ice from a freezingwall and which enables production of relatively thick ice flakes.

Still another object of this invention is to provide an ice makingapparatus having a rotary ice remover for removing ice from the outsideof the cylindrical freezing wall and which ice remover has an improvedarrangement for centering the same with respect to the freezing wall andfor maintaining portions of the ice remover spaced from the freezingwall to produce ice flakes of preselected thickness.

Yet another object of this invention is to provide an ice makingapparatus having a rotary ice remover for removing ice from the freezingwall, in which the ice remover has a helical ice engaging surface soarranged as to generate an undulated surface of revolution as it rotatesrelative to the freezing wall.

These, together with other objects and advantages of this invention willbe better understood by reference to the following detailed descriptionwhen taken in connection with the accompanying drawings wherein:

FIGURE 1 is a sectional view through the head of an ice making apparatusembodying the present invention, with the refrigerating apparatus andliquid level controls shown diagrammatically;

FIG. 2 is a transverse sectional view taken on the plane Z-Z of FIG. 1;

FIG. 3 is a fragmentary longitudinal sectional view 3,320,769 PatentedMay 23, 1967 through the head of an ice making apparatus taken on theplane 3-3 of FIG. 1;

FIG. 4 is a sectional view taken on the plane 4-4 of FIG. 5 through thehead of an ice making apparatus having a modified form of ice remover;

FIG. 5 is a transverse sectional view taken on the plane 5-5 of FIG. 4;

FIG. 6 is a sectional view taken on the plane 6-6 of FIG. 7 through thehead of an ice making apparatus having still another for-m of iceremover;

FIG. 7 is a transverse sectional view taken on the plane 7-7 of FIG. 6;

FIG. 8 is a side elevational view of the ice remover of FIG. 6; and

FIG. 9 is a sectional view through the ice remover taken on the plane9-9 of FIG. 8.

The ice making apparatus in general includes a freezing wall havingmeans for refrigerating the same sufficient to freeze a layer of waterthereon, a means for supplying water to the freezing wall, a rotary iceremover having an ice engaging surface mounted for rotation relative tothe freezing wall to remove ice therefrom, and a drive mechanism forrotatably driving the ice remover. In accordance with the presentinvention, the ice engaging surface of the ice remover is preferablymade helical with a noncircular configuration, as viewed in a directionaxially of the rotatable ice remover, so that different portions of theice engaging surface are spaced relatively different distances from thefreezing wall and generate a non-cylindrical or undulated surface ofrevolution as it rotates relative to the freezing wall.

Reference is now made more specifically to the embodiment of theinvention shown in FIGS. 1-3 of the accompanying drawings. The icemaking apparatus preferably employs an internal evaporator including atubular shell 10 defining a cylindrical freezing wall 11 on the outersurface thereof. The shell is herein shown closed at one end by athickened wall 12 and at the other end by a plug 13 which advantageouslyextends inwardly from one end of the tubular wall 10 and defines asealing face 13a spaced inwardly from the end of the freezing wall. Anysuitable means may be provided for controlling the flow of refrigerantto and through the evaporator to cool the freezing wall thereof and, asdiagrammatically shown herein, a refrigerating apparatus including acompressor 14, condenser 15 and refrigerant expansion control 16connected to refrigerant supply and return lines 17 and 18 respectively,and which supply return lines extend into the evaporator. Therefrigerant supply line 17 is conveniently formed with a reverse bend17a at its inner end to direct the incoming refrigerant downwardlytoward the bottom of the evaporator compartment, to thereby agitate theliquid therein and prevent the accumulation of oil and the like in thebottom of the evaporator. The return line 18 preferably extends to apoint adjacent the upper end of the evaporator and has its return inlet18a disposed adjacent the upper end of the compartment to return thegaseous or expanded refrigerant to the compressor.

The water to be frozen is preferably supplied to the freezing wall byimmersing the same in the Water and, for this purpose, there is providedan outer liquid jacket or vessel 25. Conveniently, the evaporator isfor-med with an enlarged head 26 at one end, which head extendsoutwardly and defines an annular wall 27 spaced outwardly from thefreezing wall 11 and a radial shoulder or stop 28. The liquid vessel 25is conveniently in the form of a sleeve 29 which surrounds the annularwall 27 and is sealed thereto as by an O-ring gasket 31. The waterjacket is detachably mounted on the base 26 of the evaporator tofacilitate cleaning of the apparatus and, as shown, is formed with anoutwardly extending flange 32.

hich is axially supported by engagement with the shoul- :r 28 on thebase, and the water jacket is detachably :cured in position on the baseas by headed rivets 33 hich extend through bayonet slots 34 in theflange 32. he vessel 25 defines a water reservoir around the evapratorand water is supplied to this reservoir through water inlet line 38,under the control of a float valve 39 r the like connected to a watersupply line 41. The float alve maintains a preselected upper liquidlevel L in the :ssel 25.

The rotary ice removing device 43 for removing ice om the freezing wallhas a helical ice engaging surface 3a. The ice remover is preferably inthe form of a )il which has only one end supported against axialmovelent so as to allow elongation and contraction of the )i1 under thestresses involved during ice removal. As rown, the coil 43 is connectedas by welding to a drive cad 44 that overlies the upper end of theevaporator, ad the drive head is connected through suitable speed:duction gear mechanism 45 to a drive motor 46. As town in FIG. 1, thehead has a threaded connection at S to the output member 49 of thereduction gear mechnism and suitable thrust bearings (not shown) areproided in the gear mechanism 45, to axially support the pper end of theice remover. The ice remover drive iechanism 73 is convenientlysupported on a detachable ead 51 which extends into the upper end of thevessel to be radially centered therein, and radial bearing ieans 52 areconveniently provided between the head 51 nd the output member 49 of thedrive mechanism, to raially support the ice remover. A discharge opening53 provided in the vessel 25 adjacent its upper end to llow the flakeice to be discharged therefrom.

The ice remover is arranged so that the helical ice enaging surfacegenerates a non-cylindrical or undulated urface of revolution as itrotates relative to the freezig wall. As best shown in FIG. 2, thefreezing wall 11 l advantageously in the form of a circular cylinder torovide a smooth freezing surface to facilitate removal f ice therefromand the helical ice engaging surface on he ice remover is formed with anoncircular configuration s viewed in a direction axially of the iceremover so 1at different portions of the helical ice engaging surface respaced relatively different distances from the freezing zall. Thisnoncircular configuration can be achieved, for xa-mple, by winding thehelical coil on a noncircular manrel, or alternatively, by laterallydeforming a circular elical coil after it has been wound. In theembodiment .lustrated in FIGS. 1-3, the helical ice engaging surfacemade generally elliptical in form, as viewed in a diection axially ofthe coil, to provide a minor diameter 1 a plane through diametricallyopposite points indicated t a and b and a major diameter in a planethrough .iametrically opposite points indicated 0 and d which arengularly offset approximately 90 from the plane of the lOlIltS a and b.In this embodiment, the minor diameter a selected so as to be somewhatlarger than the outer liameter of the freezing wall 11 by an amoutcorrespondng to the minimum thickness of the flake ice desired. orexample, if the minimum flake thickness desired is f the order of .01 to.03 inch, the minor diameter should xceed the outer diameter of thefreezing wall by about wice the minimum desired flake thickness. Themajor liameter is made substantially larger than the minor ditmeter, andpreferably at least double the difference beween the minor diameter ofthe ice remover and the inter diameter of the freezing wall so as toprovide an ce layer having a thickness which varies of the order of 00%or more.

As the noncircular helical ice removing surface rotates, he ice removingsurface generates a non-cylindricalor indulateclsurface of revolutionsomewhat as shown in )hantom in FIGS. 1 and 3 with the ridges of theenvelope ocated at those axial points along the evaporator that 'egisterwith the major diameter points such as c and d on the ice remover whilethe valleys correspond to those axial locations on the evaporator whichare aligned with the minor diameter points such as a and b on the iceremover. This envelope describes the thickness of thezice layer whichcan build up on the evaporator before it is engaged by the ice engagingsurface of the ice remover and, as will be seen, the ice layer can buildup to a nonuniform thickness of alternately thick and thin areas atlongitudinally spaced locations along the evaporator. This arrangementprovides relatively weaker areas in the ice layer, in the regionsadjacent the valleys, and facilitates removing the ice from theevaporator in smaller sections. It is considered that removal of ice insmaller sections from the evaporator reduces the peak torque loads onthe ice remover drive mechanism from that encountered when the entireice layer is removed at one time and, moreover, reduces the axialstresses and elongation of the ice remover.

The helical ice engaging surface of the ice remover is preferably madeblunt and noncutting so that it does not merely scrape off the surfaceof the ice layer but instead rides across the ice layer with aprogressively increasing pressure as the ice layer thickens until thepressure applied by the ice engaging surface to the frozen layer in adirection parallel to the freezing surface is sufficient to overcome thebonding force of the ice to the freezing Wall. Since the freezing wallis formed with a smooth cylindrical surface, it does not have any ridgesor valleys which would impede free removal of ice therefrom or formpockets in which scale or lime from the water can collect. Preferably,the ice engaging surface is formed as shown with'a convex cross sectionwith a radius that is large as com-.

pared to the spacing between the ice engaging surface and the freezingwall. Since the noncircular helical ice engaging surface generates anundulated surface of revolution as it rotates, the ice layer will have asimilarly undulated outer surface to thereby form ice flakes of varyingthickness.

While the helical ice engaging surface is shown in FIGS. 1-3 as havingan elliptical configuration, as viewed in a direction "axially of theice remover, the ice engaging surface can have other noncircularconfigurations, but the noncircular configurations are preferablysymmetrical with respect to the axis of rotation of the auger.

The ice making apparatus as illustrated in the embodiment of FIGS. 4 and5 is the same as that shown in FlGS. 1-3 except for the modified iceremover, and like numerals are used to designate the same partsdescribed in connection with the first embodiment. bodiment, thefreezing Wall 11 is preferably of cylindrical configurationwith acircular cross section. The'rotary ice removing device 143 for removingice from the freezing wall has a helical ice engaging surface 143a. Theice remover is preferably in the form of a helical member having one.end supported against axial movement. As shown, the helical member hasits upper end connected, as by welding to the drive head 144 thatoverlies'the upper end of the evaporator for rotation by the drive means45 relative to the evaporator.

The ice remover of this embodiment is also advantageously arranged sothat the helical ice engaging surface generates a non-cylindrical orundulated surface of revolution as it rotates relative to the freezingwall. In order, to facilitate radial balancing of the forces on the iceremover, the helical ice engaging surface is preferably formed with agenerally triangular configuration as viewed in a direction axially ofthe ice remover. As best shown in FIG. 5, the generally triangular iceremover has three inner ice engaging portions designated e, f and g onits ice engaging surface which are angularly spaced apart, and threeouter ice engaging portions m,- n and 0, intermediate the inner portionse, f and g. The inner portions 0, f and g are arranged to extendrelatively closer to the outer surface of the freezing wall 11 than theouter portions m, n and 0 and, since the aforedescribed inner por- As inthe preceding em- I tions e, f and g are spaced apart along the helicalice engaging surface, they extend closely adjacent the freezing wall inzones spaced apart in a direction paralleling the axis of the freezingwall.

In general, the ice layer can build up on the freezing wall until it isengaged by a portion of the rotary ice remover. When the ice remover isrotated, the inner and outer portions move in annular paths around thefreezing wall and the inner portions limit ice layer build-up to arelatively thin layer in the annular zones transversed by the innerportions, while the outer portions allow the ice layer to build up to arelatively thicker layer before removal. The outer portions m, n and 0are accordingly spaced radially from the freezing wall a distancecorresponding to the desired maximum flake thickness and may, forexample, be spaced of the order of .100" to /8" for relatively thickflakes. A smaller spacing could of course be used, if desired. The innerportions provide thin relatively weak areas in the ice layer at spacedpoints along the freezing wall which is considered to facilitate removalof the ice in smaller segments and thus reduce peak torque loads on theice remover drive motor. The inner portions may also advantageously beused to radially center the ice remover relative to the freezing walland for this purpose are shaped to extend closely adjacent andpreferably into engagement with the freezing wall 11. Since the innerportions are angularly spaced around the evaporator, they provide anautomatic centering action which maintains the outer portions of the iceremover radially spaced a uniform distance from the freezing wall. Thisprovides better control over the flake thickness by inhibiting lateralmovement of the ice remover relative to the freezing wall during iceremoval.

The noncircular configuration of the ice remover 143 can conveniently beachieved by winding the helical member on a mandrel having the generalconfiguration desired. The outer portions m, n and 0 of the ice removerare conveniently of arcuate configuration as viewed in an axialdirection with a radius exceeding that of the freezing wall by thedesired flake thickness so that the outer portions provide generallyuniform flake thickness in the zones circumscribed thereby. In the formshown, the inner portions extend generally along lines tangent to thefreezing wall. The outer periphery 143b of the helical member can beground after forming to provide a generally circular outer periphery onthe ice remover as shown in FIG. 5. As shown in FIG. 4, the helicalmember 143 has a relatively higher helix angle than that used in FIGS.1-3 and this increases the axial spacing between zones traversed by theinner portions of the ice remover.

The ice making apparatus shown in the embodiment of FIGS. 6-9 is alsothe same as that described in connection With FIGS. l3 except for theice remover, and like numerals are used to designate the same parts. Asin the preceding embodiments, the freezing wall 11 is preferably ofcylindrical configuration with a circular cross section. The rotary iceremover 243 is preferably in the form of a helical member secured to adrive member 244 and having helical ice engaging surface 243a. The iceremover has a plurality of protuberances, preferably three in number anddesignated 244a244c, at points spaced along the ice engaging surface,which protuberances extend inwardly from the ice engaging surface 243aand define inner ice engaging portions. As will be seen from FIG. 7, theice engaging surface 243a with the protuberances 244ac thereon has anoncircular configuration as viewed in an axial direction. However, theprotuberances are preferably provided only at certain locations on theice engaging surface, as described hereinafter, and are arranged in thesame position on each convolution. The protuberances are angularlyspaced apart about the axis of the ice remover and the threeprotuberances are preferably employed and located at points angularlyspaced apart about 120 from each other as viewed in an axial directionshown in FIG. 7. The protuberances are also spaced along the helical iceengaging surface so that they are spaced apart in a direction parallelto the axis of the ice remover and, preferably, are located to engagethe freezing wall at a point approximately midway of the length of thefreezing wall and at points about half way between the mid-point andeach end of the freezing wall, as shown in FIG. 6. One of theprotuberances such as 24% can be readily located at approximately themidpoint of the freezing wall. However, the location of the otherprotuberances in a direction axially of the ice remover must becorrelated with the aforedescribed desideratum that the protuberances beangularly located at approximately intervals. With the helical ice.remover shown, the desired axial location of the other protuberances244a and 2440 is approximately achieved by locating these lastprotuberances about 240 from the protuberance 244b, measured in adirection along the helix. In other words, the several protuberances arepreferably spaced apart along the helical member 120 or multiples ofthat angle, depending on the number of convolutions in the helicalmember, to the end that the protuberances engage the freezing alladjacent its midpoint and at two other locations intermediate themidpoint and each end of the ice remover. For very long freezing wallsand ice removers, a greater number of protuberances may be used, ifdesired.

The ice engaging surface 24301 is radially spaced from the freezing walla distance corresponding to the desired flake thickness and may, forexample, be spaced of the order of .100" to .125 for relatively thickflakes. A smaller spacing could of course be used, if desired. Theprotuberances preferably extend into engagement with the freezing wallto radially center the ice remover and maintain a uniform spacing of theice engaging surface from the freezing wall. The proturbances arepreferably formed of a material which minimizes friction and wear on thefreezing Wall and the latter is also preferably formed of awear-resistant material. For example, the freezing wall can be formed ofa metal such as Monel metal which is corrosion resistant and theprotuberances can be formed of a different material. The protuberancescan be formed of metal secured or deposited as by welding on the iceremover or may be formed of a suitable plastic such as nylon secured asshown in FIG. 9 by embedding in a recess or socket 245 in the iceremover. A means such as a set screw 246 is advantageously threaded intothe socket to enable adjustment of the protuberances in a directionradially of the ice remover to accommodate wear and to enable radialcentering of the ice remover.

As will be seen, the helical ice engaging surface 243a With theprotuberances thereon defines a noncircular ice engaging surface which,when the ice remover is rotated, generates a non-cylindrical orundulated surface of revolution about the freezing wall. Since theprotuberances are small and spaced far apart along the ice remover, theundulated surface generated by the ice remover has wide flat bands inthe zones traversed by the surface 243a and relatively narrow valleys inthe bones traversed by the.

protuberances. This provides weakened areas in the ice layer at spacedpoints therealong which are considered to facilitate i-ce removal.Moreover, the protuberances also produce a centering action on the iceremover.

While the principles of the invention have been described above inconnection with specific apparatus, it is to be understood that thisdescription is made only by way of example and not as a limitation tothe scope of the invention.

I claim:

1. In an apparatus for producing flake ice including an evaporatorhaving a cylindrical freezing wall and means for refrigerating the samesufficient to freeze water thereon, means for supplying Water to befrozen to said freezing wall, a rotary ice remover supported for axial 7tation relative to said cylindrical freezing wall and havg a helical iceengaging surface, and means for rotatay driving said ice remover,characterized in that the lindrical freezing wall has a circularconfiguration as :wed in axial direction and the helical ice engagingsurce has a noncircular configuration as viewed in a diction axially ofthe ice remover whereby different porms of the helical ice engagingsurface are spaced relaely different distances from the freezing walland genate an undulated surface of revolution as the ice reover rotatesrelative to the freezing wall.

2. In an apparatus for producing flake ice including an 'aporator havingan outer cylindrical freezing wall and eans for refrigerating the samesuflicient to freeze water ereon, means for supplying water to be frozento said lter freezing wall, an annular ice remover supported -r axialrotation relative to said cylindrical freezing wall 1d having aninternal helical ice engaging surface spaced om said freezing wall andextending therearound, and eans for rotatably driving said annular iceremover, iaracterized in that the cylindrical freezing wall has a rcularconfiguration as viewed in an axial direction and e helical ice engagingsurface has a noncircular conguration as viewed in a direction axiallyof the ice reover whereby different portions of the helical ice engaggsurface are spaced relatively different distances from e freezing walland generate an undulated surface of volution as the ice remover rotatesrelative to the freezg wall.

3. An apparatus according to claim 2 in which the hell- .1 ice engagingsurface has a generally elliptical conguration as viewed in a directionaxially of the an- 112.1 ice remover.

4. An apparatus according to claim 2 in which the ajor internal diameterof helical'ice engaging surface :ceeds the minor internal diameter by anamount at ast equal to the difference between the minor internal ,ameterof the ice engaging surface and the outer diamer of the freezing wall.

5. An apparatus according to claim 2 in which the ice :mover comprisesan axially expansible and contractible :lical coil.

6. An. apparatus according to claim 2 in which the .eans for supplyingliquid to the freezing wall includes vessel spaced from the freezingwall for containing quid to thereby immerse the freezing wall in theliquid.

7. An apparatus according to claim 2 in which the elical ice removingsurface has a convex cross section.

8. An apparatus according to claim 2 wherein said e engaging surface hasa generally triangular configuliiOIl as viewed in a direction axially ofthe annular ice smover.

9. An apparatus according to claim 2 wherein said ice igaging surfacehas at least three portions located at oints spaced apart along thehelical ice engaging surface ltermediate the ends thereof which portionsextend into inning engagement with the cylindrical freezing wall, ridlast mentioned portions being angularly spaced aproximately uniformlyabout the axis of the ice remover radially center the ice remover on thefreezing wall.

10. In an apparatus for producing flake ice including a evaporatorhaving an outer cylindrical freezing wall nd means for refrigerating thesame sufificient to teeze water thereon, means for supplying water to beozen to said outer freezing wall,v an annular ice re- 1over supportedfor axial rotation relative to said freez- 1g wall and having aninternal helical ice engaging surextending around the freezing wall, andmeans for otatably driving said annular ice remover, characterized 1that the cylindrical freezing wall has a circular conguration as viewedin an axial direction and said helical :e engaging surface has portionsthereof spaced radial- I from said freezing wall according to thedesired ice ake thickness and other portions intermediate said firstientioned portions which extend relatively closer to said cylindricalfreezing wall at points spaced apart axially along the freezing wallwhereby said ice engaging surface generates a non-cylindrical surface ofrevolution as the ice remover rotates relative to the freezing wall.

11. An apparatus according to claim 10 wherein said other portions ofsaid ice engaging surface extend into engagement with said cylindricalfreezing wall and are disposed at least at three different angularlocations about the annular ice remover to radially center the iceremover on the freezing wall.

12. An apparatus according to claim 10 wherein said other portions ofsaid ice engaging surface are arranged in substantial radial symmetry asviewed along the axis of the annular ice remover and are spaced apart ina direction parallel to the axis of the ice remover.

13. An apparatus according to claim 12 wherein said other portions ofsaid ice engaging surface extend into engagement with said cylindricalfreezing wall to radially center the ice rernover on the freezing wall.

14. In an apparatus for producing flake ice including an evaporatorhaving an outer cylindrical freezing wall and means for refrigeratingthe same suflicient to freeze water thereon, means for supplying waterto be frozen to said outer freezing wall, an annular ice removerextending around said freezing wall and having inner ice engagingsurface portions spaced from said freezing wall a distance correspondingto the desired flake thickness, the improvement comprising meansdefining evaporator engaging protuberances on said annular ice removerintermediate the ends thereof, said evaporator engaging protuberancesextending radially inwardly from said ice engaging surface portions anddisposed at least at three different angular locations about the axis ofthe annular ice remover to radially center the ice remover on thefreezing wall, said protuberances being spaced apart in a directionparalleling the axis of said annular ice remover. to engage saidfreezing wall in zones spaced apart axially along the freezing wall.

15. An apparatus according to claim 14 including means for adjustingsaid protuberances in a direction radially of the ice remover.

16. In an apparatus for producing flake ice including an evaporatorhaving an outer cylindrical freezing wall and means for refrigeratingthe same sufficient to freeze water thereon, means for supplying waterto be frozen to said outer freezing wall, a helical ice removerextending around the outer freezing wall and supported for axialrotation relative thereto, means for driving said ice remover,characterized in that the cylindrical freezing wall has a circularconfiguration as viewed in an axial direction and the inner surface ofthe helical ice remover has ice engaging portions at locations spacedalong the helical ice remover which ice engaging portions extend closelyadjacent the outer freezing wall and other ice enging portionsintermediate said first mentioned ice engaging portions which are spacedradially from the freezing wall a distance greater than the spacing ofsaid first mentioned portions, said first mentioned ice engagingportions, during rotation of the helical ice remover, traversingcircular paths intermediate the circular paths traversed by said otherice engaging portion whereby the inner surface of the helical iceremover generates a noncylindrical surface of revolution as the iceremover is rotated relative to the freezing wall.

17. In an apparatus for producing flake ice including an evaporatorhaving an outer cylindrical freezing wall and means for refrigeratingthe same .suflicient to freeze water thereon, means for supplying waterto be frozen to said outer freezing wall, a helical ice removerextending around the outer freezing wall and supported for axialrotation relative thereto, and means for driving said ice remover, theimprovement wherein said helical ice engaging surface the majorportionof which is spaced radially from said freezing wall a distancecorresponding to the desired flake thickness and said helical ic-e re- 910 mover has at least three evaporator engaging protuber- ReferencesCited by the Examiner ances extending radially inwardly from the iceengaging UNITED STATES PATENTS surface at spaced locations along thehelical ice engag- 3 049 895 8/1962 Larson et a1 62 354 ing surface,said protuberances being disposed at least 3101598 8/1963 Ross 62 71 atthree different angular locations about the axi of the 5 ice remover andbeing spaced apart in a direction parallel- References Cited by theApplicant ing the axis of the ice remover to engage said freezing UNITEDSTATES PATENTS Wall in zones spaced apart along the freezing Wall.3,034,317 5/1962 Schneider et a1 18. An apparatus according to claim 17wherein said 3,143,865 8/1964 ROSS. protuberances are located to engagethe freezing wall 1 4 at zones spaced approximately uniformly along the-freez- ROBERT O LEARY 1mm y Examme' ing Wall. W. E. WAYNER, AssistantExaminer.

1. IN AN APPARATUS FOR PRODUCING FLAKE ICE INCLUDING AN EVAPORATORHAVING A CYLINDRICAL FREEZING WALL AND MEANS FOR REFRIGERATING THE SAMESUFFICIENT TO FREEZE WATER THEREON, MEANS FOR SUPPLYING WATER TO BEFROZEN TO SAID FREEZING WALL, A ROTARY ICE REMOVER SUPPORTED FOR AXIALROTATION RELATIVE TO SAID CYLINDRICAL FREEZING WALL AND HAVING A HELICALICE ENGAGING SURFACE, AND MEANS FOR ROTATABLY DRIVING SAID ICE REMOVER,CHARACTERIZED IN THAT THE CYLINDRICAL FREEZING WALL HAS A CIRCULARCONFIGURATION AS VIEWED IN AXIAL DIRECTION AND THE HELICAL ICE ENGAGINGSURFACE HAS A NONCIRCULAR CONFIGURATION AS VIEWED IN A DIRECTION AXIALLYOF THE ICE REMOVER WHEREBY DIFFERENT PORTIONS OF THE HELICAL ICEENGAGING SURFACE ARE SPACED RELATIVELY DIFFERENT DISTANCES FROM THEFREEZING WALL AND GENERATE AN UNDULATED SURFACE OF REVOLUTION AS THE ICEREMOVER ROTATES RELATIVE TO THE FREEZING WALL.